U.S. patent application number 13/187934 was filed with the patent office on 2013-01-24 for method of sharing information between base stations associated with different network technologies and the base stations.
This patent application is currently assigned to ALCATEL-LUCENT TELECOM LTD.. The applicant listed for this patent is Ruth Gayde, John MacNamara, Philip Sapiano, Mark Skeates, Zhibi Wang. Invention is credited to Ruth Gayde, John MacNamara, Philip Sapiano, Mark Skeates, Zhibi Wang.
Application Number | 20130023301 13/187934 |
Document ID | / |
Family ID | 46516852 |
Filed Date | 2013-01-24 |
United States Patent
Application |
20130023301 |
Kind Code |
A1 |
Wang; Zhibi ; et
al. |
January 24, 2013 |
METHOD OF SHARING INFORMATION BETWEEN BASE STATIONS ASSOCIATED WITH
DIFFERENT NETWORK TECHNOLOGIES AND THE BASE STATIONS
Abstract
In one embodiment, the method includes establishing, at a first
base station, at least one interface with a second base station.
The first and second base stations are associated with different
network technologies, and at least one of the first and second base
stations is a small cell base station. A small cell base station
has a coverage area smaller than and at least partially overlapped
by a coverage area of a macro base station. The method further
includes one of (i) sending information from the first base station
to the second base station over the interface, and (ii) receiving
information at the first base station from the second base station
over the interface.
Inventors: |
Wang; Zhibi; (Woodridge,
IL) ; Gayde; Ruth; (Naperville, IL) ; Skeates;
Mark; (Bath, GB) ; MacNamara; John; (Orland
Park, IL) ; Sapiano; Philip; (Corsham, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Wang; Zhibi
Gayde; Ruth
Skeates; Mark
MacNamara; John
Sapiano; Philip |
Woodridge
Naperville
Bath
Orland Park
Corsham |
IL
IL
IL |
US
US
GB
US
GB |
|
|
Assignee: |
ALCATEL-LUCENT TELECOM LTD.
Swindon
NJ
ALCATEL-LUCENT USA INC.
Murray Hill
|
Family ID: |
46516852 |
Appl. No.: |
13/187934 |
Filed: |
July 21, 2011 |
Current U.S.
Class: |
455/525 ;
455/507 |
Current CPC
Class: |
H04W 92/20 20130101 |
Class at
Publication: |
455/525 ;
455/507 |
International
Class: |
H04W 36/00 20090101
H04W036/00; H04B 7/00 20060101 H04B007/00 |
Claims
1. A method of sharing information between base stations associated
with different network technologies, comprising: establishing, at a
first base station, at least one interface with a second base
station, the first and second base stations being associated with
different network technologies, at least one of the first and
second base stations being a small cell base station, the small
cell base station having a coverage area smaller than and at least
partially overlapped by a coverage area of a macro base station;
and one of (i) sending information from the first base station to
the second base station over the interface, and (ii) receiving
information at the first base station from the second base station
over the interface.
2. The method of claim 1, wherein the first and second base
stations are both small cell base stations.
3. The method of claim 1, wherein the first base station is a small
cell base station and the second base station is a macro base
station.
4. The method of claim 1, wherein the first base station is a macro
base station and the second base station is a small cell base
station.
5. The method of claim 1, wherein the information is neighbor
information.
6. The method of claim 1, wherein the information is session
information.
7. The method of claim 1, wherein the information is handoff
information.
8. The method of claim 1, wherein the information is data
traffic.
9. The method of claim 1, wherein the information is at least one
of location information, routing information, and tracking area
information.
10. The method of claim 1, wherein the information pertains to a
transmit footprint of one of the first and second base
stations.
11. The method of claim 1, further comprising: determining, at the
first base station, co-located base stations associated with
technologies different from the first base station; and wherein the
second base station is one of the determined co-located base
stations.
12. The method of claim 11, wherein the determining includes
receiving operator input indicating the co-located base stations
associated with technologies different from the first base
station.
13. The method of claim 11, wherein the determining is performed
according to automatic discovery process.
14. The method of claim 13, wherein the automatic discovery process
comprises: sending, from the first base station, a location of the
first base station to a server; and receiving, at the first base
station, a report of the co-located base stations associated with
technologies different from the first base station.
15. The method of claim 11, wherein at least one co-located base
station has an antenna on a same support structure as the first
base station.
16. The method of claim 11, wherein at least one co-located base
station has electronics housed in a same enclosure as the first
base station.
17. The method of claim 11, wherein at least one co-located base
station shares a backhaul connection with the first base
station.
18. The method of claim 11, wherein at least one co-located base
station is separated by a distance less than a threshold
distance.
19. A method of sharing information between base stations
associated with different network technologies, comprising:
establishing, at a first base station, at least one communication
path to a second base station that by-passes a wireless core
network, the first and second base stations being associated with
different network technologies, at least one of the first and
second base stations being a small cell base station, the small
cell base station having a coverage area smaller than and at least
partially overlapped by a coverage area of a macro base station;
and one of (i) sending information from the first base station to
the second base station over the interface, and (ii) receiving
information at the first base station from the second base station
over the interface.
20. A small cell base station configured to establish at least one
interface with an other base station, the small cell base station
and the other base station being associated with different network
technologies, the small cell base station having a coverage area
smaller than and at least partially overlapped by a coverage area
of a macro base station; and the small cell base station configured
to one of (i) send information to the other base station over the
interface, and (ii) receive information from the other base station
over the interface.
21. A macro base station configured to establish at least one
interface with a small cell base station, the small cell base
station and the macro base station being associated with different
network technologies, the small cell base station having a coverage
area smaller than and at least partially overlapped by a coverage
area of the macro base station; and the macro cell base station
configured to one of (i) send information to the small cell base
station over the interface, and (ii) receive information from the
small cell base station over the interface.
Description
BACKGROUND OF THE INVENTION
[0001] The wireless industry is experiencing ever increasing growth
in data and service traffic. Smart phones and data devices are
demanding more and more from wireless networks. To off-load the
traffic in dense populated areas and increase indoor coverage,
small cells have become a feasible solution. Namely, heterogeneous
networks (HetNets) are now being developed wherein cells of smaller
footprint size are embedded within the coverage area of larger
macro cells or at least partially overlapped by the larger macro
cells, primarily to provide increased capacity in targeted areas of
data traffic concentration. Such heterogeneous networks try to
exploit the spatial variations in user (and traffic) distribution
to efficiently increase the overall capacity of the wireless
network. Those smaller-sized cells are typically referred to as
small cells in contrast to the larger and more conventional macro
cells.
[0002] Also, wireless operators are using multiple technologies
because of reasons such as merger, technology advancement, legacy
customer retention, new spectrum availability, etc. The small cells
used therefore will be a combination of small cells operating
according to different technologies or standards, such as WCDMA,
LTE, etc. Currently there is no standard way to share information
between co-located small cells of different technologies, even if
they are inside the same physical enclosure, or of sharing
information between a co-located small cell and a macro cell of
different technologies. Currently, information sharing with small
cell elements (e.g., base stations) traverses through the core
network of each technology. This causes several issues and
problems, such as delay, increased network load, increased cost,
and bad user experience.
SUMMARY OF THE INVENTION
[0003] At least one embodiment relates to method of sharing
information between base stations associated with different network
technologies.
[0004] In one embodiment, the method includes establishing, at a
first base station, at least one interface with a second base
station. The first and second base stations are associated with
different network technologies, and at least one of the first and
second base stations is a small cell base station. A small cell
base station has a coverage area smaller than and at least
partially overlapped by a coverage area of a macro base station.
The method further includes one of (i) sending information from the
first base station to the second base station over the interface,
and (ii) receiving information at the first base station from the
second base station over the interface.
[0005] For example, the first and second base stations may both be
small cell base stations, the first base station may be a small
cell base station and the second base station may be a macro base
station, or the first base station may be a macro base station and
the second base station may be a small cell base station.
[0006] The information may be neighbor information, session
information, handoff information, data traffic, location
information, routing information, tracking area information, and/or
pertain to a transmit footprint of one of the first and second base
stations.
[0007] In one embodiment, the method further includes determining,
at the first base station, co-located base stations associated with
technologies different from the first base station. In this
embodiment, the second base station is one of the determined
co-located base stations.
[0008] For example, the determining may be based on operator input
indicating the co-located base stations associated with
technologies different from the first base station.
[0009] Alternatively, the determining may be performed according to
automatic discovery process.
[0010] In one embodiment, at least one co-located base station has
an antenna on a same support structure as the first base
station.
[0011] In another embodiment, at least one co-located base station
has electronics housed in a same enclosure as the first base
station.
[0012] In a further embodiment, at least one co-located base
station shares a backhaul connection with the first base
station.
[0013] In a still further embodiment, at least one co-located base
station is separated by a distance less than a threshold
distance.
[0014] Another embodiment of the method includes establishing, at a
first base station, at least one communication path to a second
base station that by-passes a wireless core network. Namely, the
communication path does not include a core network. The first and
second base stations are associated with different network
technologies, and at least one of the first and second base
stations being a small cell base station. The small cell base
station has a coverage area smaller than and at least partially
overlapped by a coverage area of a macro base station. The method
further includes one of (i) sending information from the first base
station to the second base station over the interface, and (ii)
receiving information at the first base station from the second
base station over the interface.
[0015] At least one embodiment also relates to a base station.
[0016] In one embodiment, a small cell base station is configured
to establish at least one interface with an other base station. The
small cell base station and the other base station are associated
with different network technologies, and the small cell base
station has a coverage area smaller than and at least partially
overlapped by a coverage area of a macro base station. The small
cell base station is configured to one of (i) send information to
the other base station over the interface, and (ii) receive
information from the other base station over the interface.
[0017] In another embodiment, a macro base station is configured to
establish at least one interface with a small cell base station.
The small cell base station and the macro base station are
associated with different network technologies, and the small cell
base station has a coverage area smaller than and at least
partially overlapped by a coverage area of the macro base station.
The macro cell base station is configured to one of (i) send
information to the small cell base station over the interface, and
(ii) receive information from the small cell base station over the
interface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The present invention will become more fully understood from
the detailed description given herein below and the accompanying
drawings, wherein like elements are represented by like reference
numerals, which are given by way of illustration only and thus are
not limiting of the present invention and wherein:
[0019] FIG. 1 illustrates a portion of a multiple technology
wireless architecture.
[0020] FIG. 2 illustrates a flow chart of a method for sharing
information according to an example embodiment.
DETAILED DESCRIPTION OF THE EMBODIMENTS
[0021] Illustrative embodiments are described below. In the
interest of clarity, not all features of an actual implementation
are described in this specification. It will of course be
appreciated that in the development of any such actual embodiment,
numerous implementation-specific decisions should be made to
achieve the developers' specific goals, such as compliance with
system-related and business-related constraints, which will vary
from one implementation to another. Moreover, it will be
appreciated that such a development effort might be complex and
time-consuming, but would nevertheless be a routine undertaking for
those of ordinary skill in the art having the benefit of this
disclosure.
[0022] In the following description, for purposes of explanation
and not limitation, specific details are set forth such as
particular architectures, interfaces, techniques, etc., in order to
provide a thorough understanding of the embodiments. However, it
will be apparent to those skilled in the art that the embodiments
may be practiced in ways that depart from these specific details.
In some instances, detailed descriptions of well-known devices,
circuits, and methods are omitted so as not to obscure the
description of the embodiments with unnecessary detail. All
principles, aspects, etc. of the embodiments, as well as specific
examples thereof, are intended to encompass both structural and
functional equivalents thereof. Additionally, it is intended that
such equivalents include both currently known equivalents as well
as equivalents developed in the future.
[0023] Example embodiments are discussed herein as being
implemented in a suitable computing environment. Although not
required, exemplary embodiments will be described in the general
context of computer-executable instructions, such as program
modules or functional processes, being executed by one or more
computer processors or CPUs. Generally, program modules or
functional processes include routines, programs, objects,
components, data structures, etc. that performs particular tasks or
implement particular abstract data types. The program modules and
functional processes discussed herein may be implemented using
existing hardware in existing communication networks. For example,
program modules and functional processes discussed herein may be
implemented using existing hardware at existing network elements or
control nodes. Such existing hardware may include one or more
digital signal processors (DSPs),
application-specific-integrated-circuits, field programmable gate
arrays (FPGAs) computers or the like.
[0024] Portions of the embodiments and corresponding detailed
description are presented in terms of software, or algorithms and
symbolic representations of operations on data bits within a
computer memory. These descriptions and representations are the
ones by which those of ordinary skill in the art effectively convey
the substance of their work to others of ordinary skill in the art.
An algorithm, as the term is used here, and as it is used
generally, is conceived to be a self-consistent sequence of steps
leading to a desired result. The steps are those requiring physical
manipulations of physical quantities. Usually, though not
necessarily, these quantities take the form of optical, electrical,
or magnetic signals capable of being stored, transferred, combined,
compared, and otherwise manipulated. It has proven convenient at
times, principally for reasons of common usage, to refer to these
signals as bits, values, elements, symbols, characters, terms,
numbers, or the like.
[0025] It should be borne in mind, however, that all of these and
similar terms are to be associated with the appropriate physical
quantities and are merely convenient labels applied to these
quantities. Unless specifically stated otherwise, or as is apparent
from the discussion, terms such as "processing" or "computing" or
"calculating" or "determining" or "displaying" or the like, refer
to the action and processes of a computer system, or similar
electronic computing device, that manipulates and transforms data
represented as physical, electronic quantities within the computer
system's registers and memories into other data similarly
represented as physical quantities within the computer system
memories or registers or other such information storage,
transmission or display devices.
[0026] Note also that the software implemented aspects of the
invention are typically encoded on some form of program storage
medium or implemented over some type of transmission medium. The
program storage medium may be solid state (e.g., flash memory),
magnetic (e.g., a floppy disk or a hard drive) or optical (e.g., a
compact disk read only memory, or "CD ROM"), and may be read only
or random access. Similarly, the transmission medium may be twisted
wire pairs, coaxial cable, optical fiber, over-the-air or some
other suitable transmission medium known to the art. The
embodiments are not limited by these aspects of any given
implementation.
[0027] It will be understood that, although the terms first,
second, etc. may be used herein to describe various elements, these
elements should not be limited by these terms. These terms are only
used to distinguish one element from another. For example, a first
element could be termed a second element, and, similarly, a second
element could be termed a first element, without departing from the
scope of example embodiments of the present invention. As used
herein, the term "and/or" includes any and all combinations of one
or more of the associated listed items.
[0028] It will be understood that when an element is referred to as
being "connected" or "coupled" to another element, it can be
directly connected or coupled to the other element or intervening
elements may be present. In contrast, when an element is referred
to as being "directly connected" or "directly coupled" to another
element, there are no intervening elements present. Other words
used to describe the relationship between elements should be
interpreted in a like fashion (e.g., "between" versus "directly
between", "adjacent" versus "directly adjacent", etc.).
[0029] The terminology used herein is for the purpose of describing
particular embodiments only and is not intended to be limiting of
example embodiments of the invention. As used herein, the singular
forms "a", "an" and "the" are intended to include the plural forms
as well, unless the context clearly indicates otherwise. It will be
further understood that the terms "comprises", "comprising,",
"includes" and/or "including", when used herein, specify the
presence of stated features, integers, steps, operations, elements,
and/or components, but do not preclude the presence or addition of
one or more other features, integers, steps, operations, elements,
components, and/or groups thereof.
[0030] It should also be noted that in some alternative
implementations, the functions/acts noted may occur out of the
order noted in the figures. For example, two figures shown in
succession may in fact be executed substantially concurrently or
may sometimes be executed in the reverse order, depending upon the
functionality/acts involved.
[0031] The embodiments will now be described with reference to the
attached figures. Various structures, systems and devices are
schematically depicted in the drawings for pui poses of explanation
only and so as to not obscure the embodiments with details that are
well known to those skilled in the art. Nevertheless, the attached
drawings are included to describe and explain illustrative
examples. Where applicable, the words and phrases used herein
should be understood and interpreted to have a meaning consistent
with the understanding of those words and phrases by those skilled
in the relevant art.
[0032] As used herein, the term "access terminal" may be considered
synonymous to, and may hereafter be occasionally referred to, as a
client, mobile station, mobile, mobile unit, mobile station, mobile
user, user equipment (UE), subscriber, user, remote station,
receiver, etc., and may describe a remote user of wireless
resources in a wireless communication network. The wireless
resource may be a mobile phone, wireless equipped personal
computer, etc. The term "base station" may be considered synonymous
to and/or referred to as a base transceiver station (BTS), NodeB,
extended Node B, femto cell, access point, etc. and may describe
equipment that provides the radio baseband functions for data
and/or voice connectivity between a network and one or more
users.
[0033] As is well-known in the art, each of a access terminal and a
base station may have transmission and reception capabilities.
Transmission from the base station to the access terminal is
referred to as downlink or forward link communication. Transmission
from the access terminal to the base station is referred to as
uplink or reverse link communication.
[0034] FIG. 1 illustrates a portion of a multiple technology
wireless architecture including macro cells and small cells
according to an example embodiment. In particular, FIG. 1
illustrates two different wireless technologies having associated
macro and small cells. The wireless technologies represented are
WCDMA and LTE. It should be understood that the embodiments are not
limited to two different wireless technologies. Instead, the
embodiments are applicable to any combination of two or more
different wireless technologies. Also, the embodiments are not
limited to the wireless technologies of WCDMA and LTE.
[0035] As shown in FIG. 1, a small cell base station 200 operating
according WCDMA communicates over a first standard interface SI1
with a core network 102 of WCDMA wireless network 100. Besides the
core network 102, the WCDMA wireless network 100 also includes a
radio access network 104 that includes one or more macro cells. As
used herein, the terminology "cell" refers to the coverage area as
well as the base station serving the coverage area. Furthermore, it
will be understood that each cell has an associated base station.
While not shown, the radio access network 104 may also include
radio network controllers managing one or more base stations. The
core network 102 provides system level control over one or more
radio access networks 104, and provides communication gateways to
other networks such as the internet 130.
[0036] FIG. 1 further shows that a LTE small cell base station 210
operating according LTE, communicates over a second standard
interface SI2 with a core network 112 of a LTE, wireless network
110. Besides the core network 112, the LTE wireless network 110
also includes a radio access network 114 that includes one or more
macro cells. While not shown, the radio access network 114 may also
include radio network controllers managing one or more base
stations. The core network 112 provides system level control over
one or more radio access networks 114, and provides communication
gateways to other networks such as the internet 130.
[0037] For the purposes of discussion, it will be assumed that at
least one macro cell base station in each of the WCMDA radio access
network 104 and the LTE radio access network 114 have substantially
overlapping coverage areas. For the purposes of discussion, it will
further be assumed that each of the small cell WCDMA base station
200 and the small cell LIE base station 210 have substantially
overlapping coverage areas that fall within or significantly
overlap with the coverage areas of the macro cell base stations.
Namely, the small cells at least partially overlap with a
corresponding macro cell. Additionally, being small cells, the
transmit power output and resultant coverage areas of these base
stations are smaller than that of the macro cells.
[0038] Conventionally, communication between small cells of the
different wireless technologies traverses the core networks of both
technologies. Similarly, communication between a small cell of one
technology and the macro cell of a different technology also
traverses the core networks of both technologies.
[0039] In one embodiment, a direct sharing interface may be
established between small cells of different wireless technologies.
Additionally, or alternatively, a direct sharing interface may be
established between a small cell and a macro cell of different
wireless technologies. For example, FIG. 1 shows a first direct
sharing interface DSI1 between the small cell base station 200
operating according to WCDMA and the small cell base station 210
operating according to LTE. As another example, FIG. 1 shows a
second direct sharing interface DSI1 between the small cell base
station 200 operating according to WCDMA and a macro cell base
station in the LTE radio network 114.
[0040] Next, establishing the direct sharing interface and sharing
of information over the established direct sharing interface will
be described in detail. FIG. 2 illustrates a flow chart of a method
for establishing the direct sharing interface and sharing of
information over the established direct sharing interface. For the
purposes of example only, the method will be described as being
performed at a small cell base station of a first network
technology. As shown, in step S20, a small cell base station
determines co-located small cell and/or macro cell base stations
operating according to network technologies different from the
first network technology.
[0041] A co-located base station may be a base station having an
antenna on a same support structure (e.g., building, light post,
tower, etc.) as the small cell base station. Alternatively, or
additionally, a co-located base station may be a base station
having electronics housed in a same enclosure as the small cell
base station. Alternatively, or additionally, a co-located base
station may be within a threshold distance of the small cell base
station. The threshold distance may be a design parameter
determined through empirical study. Alternatively, or additionally,
co-located base stations may share a physical backhaul connection
such as to an operator's core network.
[0042] In one embodiment, the small cell base station receives
operator input indicating the co-located base station(s).
[0043] In another embodiment, the small cell base station may pedal
an auto discovery operation to determine the co-located base
stations. For example, each small cell and macro cell base station
may be equipped with a global position sensor (GPS), and may report
its location to a network server. The network server may be a
server in one or more of the core networks of the different
technologies, and these servers may communicate with one another.
Alternatively, a single server may serve multiple core networks of
different technologies, and be communicatively connected to those
core networks. The server determines co-located base stations, and
sends each base station a report indicating the co-located base
stations. The server may determine base stations as being
co-located if a distance between the base stations is less than a
threshold distance. As will be appreciated, the threshold distance
may be a design parameter determined through empirical study.
Accordingly, each small cell and macro cell base station may
receive the report automatically, and/or, may request the report
from the network server.
[0044] In a further embodiment, if housed in the same enclosure,
the electronics of the base stations associated with different
technologies may share one or more communication buses, and may
poll for the presence of the other base stations.
[0045] As will be appreciated these above described embodiments for
determining co-located base stations is not exhaustive, and one or
more of these embodiments may be employed
together/concurrently.
[0046] Returning to FIG. 2, after determining the co-located base
stations of different technologies, the small cell base station
establishes direct sharing interfaces with one or more of the
co-located base stations of other network technologies in step S30.
The interface may be a physical, wireline interface or a wireless
interface. For example, when the small cell base station and the
co-located base station are disposed within the same enclosure and
share a communication bus, the interface may be a physical
interface over the bus. Alternatively, another type of physical
connection (e.g., Ethernet, etc.) may be exist and be employed for
the interface. With respect to the wireless interface, the base
stations may be configured to communicate on overhead channels (or
portions thereof) used in the various different wireless
technologies.
[0047] Establishing the direct sharing interface may performed
through a request-acknowledgement scheme where the small cell base
station sends a request message that requests the co-located base
station of the different technology become interfaced therewith. In
response, the co-located base station sends an acknowledgement
message, and the interface is established. As will be appreciated,
the request-acknowledgement scheme may be modified to include any
well-known authentication procedure. Still further, the
request-acknowledgement scheme may be modified to include
establishing the interface as an encrypted link according to any
well-known procedure.
[0048] Once the direct sharing interfaces are established, the
interfacing base stations may share information in step S40.
Namely, the small cell base station may receive information from
the co-located base station of the different technology, and/or the
small cell base station may send information to the co-located base
station of the different technology.
[0049] Various types of information may be shared. For example, the
base stations may share neighbor information. The neighbor
information may include a list of known neighboring base stations,
to facilitate self organizing networks (SONs) and/or Automatic
Neighbor Relation (ANR). ANR allows the eNodeBs to populate their
neighbor lists, by utilizing information reported by a UE on
detected LTE, WCDMA and GSM neighbors. In LTE, this functionality
is supported by all releases of UE, but in WCDMA it is not
available until much later in the standards. Because the neighbors
detected by the eNodeB are equally applicable to the WCDMA portion
of the small cell as the two units are co-located, the information
shared can be used for the WCDMA neighbor generation.
[0050] ANR can also be realized by the small cell moving into a
"Sniffing Mode," which is where the small cell receiver tunes into
the downlink frequency and decodes the neighbor cells. As this may
involve hardware impact on the RF chain, and service interruption,
it is advantageous to have only one of the small cells portions
(e.g. WCDMA) perform this function and share the result with the
other small cells (e.g. LTE).
[0051] Additionally, or alternatively, the shared information may
include session information. Session information can include the
charging information, call state, security keys and parameters, QoS
information, policy information, and etc.
[0052] Additionally, or alternatively, the shared information may
include handoff or handover information. The handoff information
can be user traffic queued at small cells, IDs such as IP address,
radio measurements, radio channel information, cell IDs, circuit
IDs, UE location, and etc.
[0053] Additionally, or alternatively, the shared information may
include data traffic (e.g., forwarded after handoff or during a
handoff).
[0054] Additionally, or alternatively, the shared information may
include location information.
[0055] Additionally, or alternatively, the shared information may
include cell load information such as uplink (UL)/downlink (DL) RF
and baseband load, number of users served etc, where the mutual
load information allows a decision upon whether to redirect UEs
from one layer to another or to the Macro layer.
[0056] Additionally, or alternatively, the shared information may
include information on the transmit footprint (e.g., pathloss at
cell edge measured by UEs) of the small cell in order to determine
whether one cell portion has a larger footprint than the other.
This information can then be used to determine whether mobility
between layers can be reliably performed through blind
handover/redirection or whether mobile assisted measurements are
required.
[0057] Additionally, or alternatively, the shared information may
include information on the location (WCDMA)/routing
(WCDMA)/tracking area (LTE) so that the two areas may be
coordinated in order to benefit from Idle Mode Signaling Reduction
(ISR) feature in LTE (TS 23.401)
[0058] By sharing info illation directly between small cells of
different technologies or between a small cell of one technology
and a macro cell of another technology, load on the core networks
may be greatly reduced. Namely, by establishing a communication
path that by-passes the core networks of the macro cells (i.e.,
excludes the core networks of the macro cells), load on the core
networks may be greatly reduced. Additionally, various processes,
such as handover, multicasting, etc. may be performed more
efficiently and with significantly less delay.
[0059] The invention being thus described, it will be obvious that
the same may be varied in many ways. Such variations are not to be
regarded as a departure from the invention, and all such
modifications are intended to be included within the scope of the
invention.
* * * * *